Documents / Case file
This is an initial Project Sign progress report dated April 1948, sent from Headquarters, Air Materiel Command at Wright-Patterson Air Force Base to the Chief of Staff, U.S. Air Force. It tabulates about 100 unidentified flying object reports received through February 1948, covering shape, size, number of objects, speed and exhaust trails. Dr. Irving Langmuir found the data insufficient for a positive identification. Headquarters judged that a low aspect ratio aircraft using boundary layer control could reproduce many of the reported characteristics.
From the source: Release of 2026-07-10 Incident: 1948, Various. This file contains an initial report from the Air Materiel Command regarding Project Sign. Project Sign was a 1948-1949 U.S. Air Force program to investigate the nature and origin of unidentified flying objects (UFO). The report details 100 UFO sightings from 1947-1948. The file also contains an article excerpted from “The Aeroplane,” an aviation-focused periodical magazine published between 1911 and 1968, titled “The Biology of the Flying Saucer.”
•Incident Observer ' s No . 1 la lb le l d le 2 3 4 5 6 7 9 Occupation 1st Lt, UJAF :,/::,gt, 0::i,v' Uninown s/sgt, USAF Pfc, USAF ~fot stated :Uaj, USAF liajor, USAF Capt, USAF Patr olman, ?ortland Police Dept. Sgt, Oregon Police Patr olman, Por tland Police Dept., former Air Force pilot Patrolman, Portland Police Dept. Pri vate pilot Patrolman, Portland Police Dept . ?ri vate pilot Capt., Harbot pilot Jo1aneuvers 1lone - horizontal fl1gnt 1"ot stated t-:et stated Not stated Flying in tight circle Horizontal anrl tipht circles Descended from an intennediate altitude in an oscillating fashion almost to the ground, then started climbing again to a very high altitude and moved off slowly in the distance. Oscillating in a downward twirl- ing movement Falling at three times the rate of a parachute Dippi nP, up and down in oscillat-- ing motion Following each otner Not stated Str aight line formation; last disc fluttered very rapidly in side-way arc Strai~ht line fonnation ; last disc fluttered very rapidly in side-way- are Discs wo'.lld oscillat e and SOl11131-' times a full disc would be vis~ ibl e, then a half-moon shape, t hen nothing at all Heatner IiOt stated .,ot stated l1ot stated ~!ot stated !fot stat'3d !lot stated Not stated Not stated ?!ot stated Not stated Clear with little or no cloud f orma tion Clear with little or no cloud forma tion Clear with little or no cloud for.na tion Clear with little or no cloud forma tion Not stated CUiqfiDE~~TIALNND 927545
Case file, from the pursue collection. The PDF is mirrored here; the original link is above. 45 pages are in the text index: search them above, or from the library's search.